检索结果-南通市图书馆

A refined representation method of the particle size distribution curve based on grading entropy

在线全文

学校读者我要写书评

暂无评论

Particuology 2024年第5期88卷 302-311页

作者： xing Li Qun chen Zhaozhao liu cheng Zhou chen Wang chen chen State Key Laboratory of Hydraulics and Mountain River Engineering College of Water Resource and HydropowerSichuan UniversityChengdu610065China

The particle size distribution(PSD)curve is an important expression of the basic properties of the *** characteristic parameters such as median particle size D_(50),effective particle size D_(10),and some combinations of characteristic parameters can only represent some points of the PSD curve,failing to represent all information of the PSD *** this paper,a fraction characteristic parameter F that could reflect the fraction size variation of the PSD curve was introduced based on grading *** a new presentation method of the A-B-F three parameters was proposed for a refined representation of the PSD *** was found that the newly constructed model not only better represents the differences in the width of PSD curves but also has a higher sensitivity than the A-B two-parameter model proposed by Lő*** PSD curves with similar distributions,the new presentation method has a higher degree of discrimination than that of the D_(50)-C_(u)-C_(c) three-parameter or the four-parameter combination G_(c) proposed by ***,the application of this new method in describing the spatial nonuniformity distribution of depositions and predicting the soil hydraulic conductivity was *** research results can provide a reference for the refined representation of PSD curves.

关键词： Grading entropy Particle size distribution curve Refined representation

Link Prediction Method Fusion with Local Structural Entropy for Directed Network

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Journal of Electronics 2024年第1期33卷 204-216页

作者： Shuxin liu Hongchang chen Lan WU Kai WANG xing LI People’s Liberation Army Strategic Support Force Information Engineering University

Link prediction utilizes accessible network information to complement or predict the network *** is an important prerequisite for link prediction which means links more likely occurs between two similar nodes. Existing methods utilize the similarity of nodes but neglect of network structure. However the link direction leads to a far more complex structure and contains more information useful than the undirected networks. Most classic methods are difficult to depict the distribution of the network structure with incidental direction so the similarity characteristics of the network structure itself are lost. In this respect, a new method of local structure entropy is proposed to depict the directed structural distribution characteristics, which can be used to evaluate the degree of local structural similarity of nodes and then applied to link prediction methods. Experimental results on 8 real directed networks show that this method is effective for both area under the receiver operating characteristic curve(AUC)and ranking-score measures, and improved predictive capacity of the baseline methodology.

关键词： Correlation Current measurement Area measurement Prediction methods Receivers Benchmark testing Entropy

A dynamic exploratory hybrid modelling framework for simulating complex and uncertain system

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Journal of Safety Science and Resilience 2024年第2期5卷 167-178页

作者： Gangqiao Wang Han xing Yongqiang chen Yi liu Institute of Big Data Inteligent Management and Decision-making College of ManagementShenzhen UniversityShenzhen 518060China School of Safety Science Tsinghua UniversityBejing 100084China Department of Mechanics and Engineering Science College of EngineeringPeking UniversityBejing 100871China

Complex disaster systems involve various components and mechanisms that could interact in complex ways and change over time,leading to significant deep *** to deep uncertainty,decision-makers have severe inadequacy of knowledge and often encounter unpredictable surprises that may emerge in the future,thus making it difficult to specify appropriate models and parameters to describe the system of *** this paper,we propose a dynamic exploratory hybrid modeling framework that fits data,models,and computational ex-periments together to simulate complex systems with deep *** the framework,one needs to develop multiple plausible models from a hybrid modeling perspective and perform enormous computational experi-ments to explore the diversity of future ***-time data is then incorporated into diverse forecasts to dynamically adjust the simulation *** ultimately enables an ongoing modeling and analysis process in which deep uncertainty would be gradually *** approach has been applied to a human-involved car-following system simulation under complex traffic *** results show that the proposed approach can improve the prediction accuracy while enhancing the sensitivity of the simulation system to uncertain changes in the system of interest.

关键词： Disaster modeling and analysis Deepuncertainty Hybrid modeling Adaptivesimulation

Iron single-atom/clusters catalysts derived from iron-rich Enteromorpha after urea-saturation for Fenton-like reaction

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2024年第3期35卷 149-152页

作者： Yujie Zhang Siyi liu Dongdong chen xing Xu School of Environmental Science and Engineering Shandong UniversityQingdao 266237China

Fabrication of single atom catalysts(SACs)by a green and gentle method is important for their practical Fenton-like *** this work,a high effective iron-based catalyst was prepared from the iron-rich Enteromorpha for NPX degradation via peroxymonosulfate(PMS).Both Fe-SACs and iron-clusters was fabricated from the intrinsic iron element in Enteromorpha after the urea *** Fe-SACs/clusters can achieve 100%of NPX oxidation within 20 min with the k_(obs)of 0.282 min^(-1).Quenching tests indicated that the radical pathways were not dominated in the catalytic systems,and strong electron transfer process can be induced in the Fe-SACs/clusters+PMS system by using the NPX as electron donor and FeSACs/clusters/PMS^*complexes as electron *** result was consistent with the phenomenon observed in the galvanic oxidation *** addition,the Fe-SACs/clusters was deposited onto the ceramic membrane(CM)by the spraying-crosslinking process to form a Fe-SACs/clusters@CM,which showed an effective and continuous NPX degradation in a heterogeneous PMS system.

关键词： SACs Iron Clusters Fenton-like reaction Enteromorpha

First-principles study on the electronic structure of Pb_(10−x)Cu_(x)(PO_(4))_(6)O(x=0,1)

在线全文

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2024年第4期171卷 66-70页

作者： Junwen Lai Jiangxu Li Peitao liu Yan Sun xing-Qiu chen Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China

Recently,Lee et *** the experimental discovery of room-temperature ambient-pressure super-conductivity in a Cu-doped lead-apatite(LK-99)(arXiv:2307.12008,arXiv:2307.12037).Remarkably,the claimed superconductivity can persist up to 400 K at ambient *** the experimental im-plication,the electronic structure of LK-99 has not yet been ***,we investigate the electronic structures of LK-99 and its parent compound using first-principles calculations,aiming to elucidate the doping effects of *** results reveal that the parent compound Pb_(10)(PO_(4))_(6)O is an insulator,while Cu doping induces an insulator-metal transition and thus volume *** band structures of LK-99 around the Fermi level are featured by a half-filled flat band and a fully-occupied flat *** two very flat bands arise from both the 2p orbitals of 1/4-occupied O atoms and the hybridization of the 3d orbitals of Cu with the 2p orbitals of its nearest-neighboring O ***,we observe four van Hove singularities on these two flat ***,we show that the flat band structures can be tuned by including electronic correlation effects or by doping different *** find that among the considered doping elements(Ni,Cu,Zn,Ag,and Au),both Ni and Zn doping result in the gap opening,whereas Au exhibits doping effects more similar to Cu than *** work establishes a foundation for fu-ture studies to investigate the role of unique electronic structures of LK-99 in its claimed superconducting properties.

关键词： First-principles calculations Density functional theory Electronic structur e Superconductivity Flat bands Strongly correlated electrons

A Data-Driven Real-Time Trajectory Planning and Control Methodology for UGVs Using LSTMRDNN

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

IEEE/CAA Journal of Automatica Sinica 2024年第5期11卷 1292-1294页

作者： Kaiyuan chen Runqi Chai Runda Zhang Zhida xing Yuanqing Xia Guoping liu Vanke School of Public Health Institute for Healthy ChinaTsinghua UniversityBeijing 100084 School of Automation Beijing Institute of TechnologyBeijing 100081 Department of Electronic and Electrical Engineering Southern University of Science and TechnologyShenzhen 518055China

Dear Editor,This letter presents a novel data-driven trajectory planning and control scheme for the unmanned ground vehicles(UGVs).A recent work[1]has demonstrated the effectiveness of approximating the optimal state ... 详细信息

关键词： LSTM UGV neural

Needs and challenges of optical atmospheric monitoring on the background of carbon neutrality in China

在线全文

学校读者我要写书评

暂无评论

Frontiers of Environmental Science & Engineering 2024年第6期18卷 49-62页

作者： Wenqing liu chengzhi xing Anhui Institute of Optics and Fine Mechanics Hefei Institutes of Physical ScienceChinese Academy of SciencesHefei 23001China

The achievement of the targets of coordinated control of PM2.5 and O3 and the carbon peaking and carbon neutrality depend on the development of pollution and greenhouse gas monitoring *** monitoring technology,based on its technical characteristics of high scalability,high sensitivity and wide-targets detection,has obvious advantages in pollution/greenhouse gases monitoring and has become an important direction in the development of environmental monitoring *** present,a system of environmental optical monitoring technology with differential optical absorption spectroscopy(DOAS),cavity ring-down spectroscopy(CRDS),light detection and ranging(LIDAR),laser heterodyne spectroscopy(LHS),tunable diode laser absorption spectroscopy(TDLAS),fourier transform infrared spectroscopy(FTIR)and fluorescence assay by gas expansion(FAGE)as the main body has been ***,with the promotion of“reduction of pollution and carbon emissions”strategy,there have been significant changes in the sources of pollution/greenhouse gases,emission components and emission concentrations,which have put forward new and higher requirements for the development of monitoring *** the future,we should pay more attention to the development of new optical monitoring techniques and the construction of stereoscopic monitoring system,the interdisciplinarity(among mathematics,physics,chemistry and biology,etc.),and the monitoring of greenhouse gases and research on atmospheric chemistry.

关键词： Pollution Greenhouse gas Optical atmospheric monitoring Needs and challenges

Research on the influences of motion characteristics of jetting projectile charge under water

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Defence Technology（防务技术） 2024年第3期33卷 411-425页

作者： xing chen Yong-gang Lu Institute of Systems Engineering China Academy of Engineering PhysicsMianyang 621900SichuanChina

Shaped charge warhead is important for enhancing the damage performance of underwater *** paper used finite element analysis software and based on JPC water penetration experiments to examine the influence of liner parameters(wall thickness,material),charge aspect ratio,and stand-off distance on the movement characteristics of JPC in *** findings reveal that the head diameter of the JPC increases and experiences significant erosion after entering the water,the effective length of the JPC in water undergoes two distinct phases:a growth phase and a decrease phase,with the velocity of the JPC decaying *** the liner thickness,stand-off distance and the charge aspect ratio can improve the erosion resistance and the velocity retention capacity of the *** optimal ranges for liner thickness and stand-off distance are 0.0363D_(k) to 0.0545D_(k)(D_(k) is the charge diameter),the stand-off distance should be within 1.0D_(k).After the charge aspect ratio higher than 1.25,the charge structure exerts minimal influence the movement characteristics of the JPC in *** density plays a crucial role in the velocity decay pattern of the JPC during *** with higher densities exhibit superior velocity retention capabilities in water,with the velocity decay pattern converging if the densities are ***,copper,tantalum and tungsten liners are deemed appropriate for underwater shaped charge ***,the results will provide an important reference for the design of underwater shaped charge warhead.

关键词： JPC Movement characteristics Underwater penetration Numerical simulation

Generation of mitochondrial replacement monkeys by female pronucleus transfer

在线全文

学校读者我要写书评

暂无评论